Week 1- Histology

Question 1

What are the roles of the ovary?

Answer 1

Produce gametes

Produce steroids- mainly oestrogen and progesterone

Question 2

Describe the structure of the ovary?

Answer 2

Has a medulla and cortex.

Question 3

Describe the medulla of the ovary?

Answer 3

Forms the core of the organ. Contains loose connective tissue, contorted arteries, veins and lymphatics. Its continuous with the hilum of the organ.

Question 4

Describe the cortex of the ovary?

Answer 4

Has scattered ovarian follicles in a highly cellular connective tissue stroma. The outer layer of the cortex is a dense connective tissue layer called the tunica albuginea, which is covered by a single layer of cuboidal cells called the germinal epithelium.

Question 5

Which layer of the ovary forms the white outer layer?

Answer 5

The tunica albuginea

Question 6

Describe the maturation of the ovary from the primordial follicle to where it is released from the ovary?

Answer 6

Primordial follicle
Primary follicle
Secondary follicle
Mature graafian follicle

Question 7

What is oogenesis?

Answer 7

Development of oocytes from oogonia.

Question 8

What is folliculogenesis?

Answer 8

Growth of the follicle, which consists of the oocyte and any associated support cells.

Question 9

Women lose oogonia and oocytes via what process?

Answer 9

Atresia.

Question 10

Describe the development of follicles before birth

Answer 10

Before birth, the oocytes undergo meiosis but halt in prophase 1. They will then undergo further meiosis at puberty and will complete meiosis II if they are fertilised.

Question 11

What will happen if an oocyte fails to associate itself with pregranulosa cells?

Answer 11

It dies.

Question 12

What happens to the pregranulosa cells if the primordial follicle enters the growth phase?

Answer 12

They are squamous before the growth phase, but become cuboidal after.

Question 13

How can you distinguish between primary follicles and oocytes?

Answer 13

The presence of cuboidal granulosa cells- termed the zona granulosa.

Question 14

Describe the cell arrangement around the primary follicle?

Answer 14

Squamous cells have proliferated to form a single layer of cuboidal cells. The cells adjacent to cuboidal cells, particularly closest to the follicle have started to develop. You can start to see the zona pellucida.

Question 15

What is the theca interna and externa and how is it formed?

What is its function?

Answer 15

The theca interna is formed by differentiation of inner layers of stromal cells.
Goes on to secrete oestrogen precursors which are then converted to oestrogen by granulosa cells.
The theca externa remains fibroblast like.

Question 16

What is the Antrum? What is it filled with? What layer does it form in?

Answer 16

As the follicle enlarges, a space called the Antrum develops.
Filled with Antrum fluid.
The granulosa layer.

Question 17

When is it classed a Graafian follicle?

Answer 17

The largest of follicles has a large Antrum,

Question 18

When does the oocyte complete meiosis I? What occurs after this?

Answer 18

One day before ovulation, the oocyte in the largest Graafian follicle will complete meiosis I. It doesn’t form two identical cells, it forms one large secondary follicle and one polar body.
The secondary oocyte then goes onto the second phase of meiosis but stops at metaphase II.

Question 19

When will the secondary follicle complete meiosis II? What else is produced in this?

Answer 19

Only completes it if fertilised

A secondary polar body.

Question 20

What is the follicular stigma?

Answer 20

The place where the follicle bulges against the side of the ovary.

Question 21

What happens after ovulation in the ovary?

Answer 21

The follicle becomes the corpus luteum. It releases oestrogen and progesterone which help prepare the uterus for implantation.

Question 22

What happens to the corpus luteum if no implantation occurs?

Answer 22

The corpus luteum becomes the corpus albicans.

Question 23

What happens to the corpus luteum if implantation occurs?

Answer 23

The placenta secretes HCG which prevents degeneration of the corpus luteum for some time so progesterone levels can be maintained.

Question 24

What are the projections of the Fallopian tubes called?

Answer 24

Fimbrae.

Question 25

How does the egg get from the ovary to the uterus?

Answer 25

Ejected from the ovary. Collected by the fimbrae of the Fallopian tubes. Moves down the Fallopian tubes by gentle peristaltic movements and currents created by the ciliated epithelium.

Question 26

Where does fertilisation usually occur?

Answer 26

In the ampulla of the Fallopian tubes.

Question 27

What type of epithelium is present in the ampulla of the Fallopian tube?

Answer 27

Simple columnar epithelium with ciliated cells and secretory cells. This is surrounded by smooth muscle.

Question 28

Describe the structure of the isthmus of the Fallopian tube?

Answer 28

Secretory epithelium with few ciliated cells. 3 layers of smooth muscle.

Question 29

Describe the structure of the uterus?

Answer 29

Endometrium- inner secretory mucosal layer. Made up of tubular secretory glands embedded in a connective tissue stroma.
Myometrium- 3 layers of smooth muscle combined with collagen and elastic tissue.
Perimetrium- outer visceral layer of loose connective tissue covered by mesothelium.

Question 30

How can the endometrium be divided? Describe each.

Answer 30

Stratum functionalis- undergoes monthly growth, degeneration and loss
Stratum basalis-reserve tissue that regenerates the functionalis.

Question 31

What happens to the stratum basalis during the proliferative layer of menstruation?

Answer 31

The stratum basalis proliferates and glands, stroma and vasculature grow- increasing the thickness of the endometrium by reconstituting the stratum functionalis.

Question 32

What happens to the layers of endometrium during the secretory phase of menstruation?

Answer 32

The glands become coiled with a corkscrew appearance and secrete glycogen.

Question 33

What happens to the layers of the endometrium during the menstruation phase?

Answer 33

Arterioles in the stratum functionalis undergo constriction, depriving the tissue of blood and causing ischaemia, with resultant tissue breakdown and leakage of blood.

Question 34

What tissues make up the cervix?

Answer 34

Mostly fibrous connective tissue covered with stratified squamous epithelium on its vaginal surface, transitioning to mucous secreting simple columnar epithelium.

Question 35

What is the significance of the transition zone in the cervix?

Answer 35

Common site of dysplagia and neoplastic changes leading to cervical carcinoma being commonest in this area.

Question 36

Describe the structure of the mucous secreting epithelium of the cervix?

Answer 36

Deeply furrowed so looks to form glands.